Apparatus for the manufacture of crude calcium cyanamid.



N. C. TOMMASI APPARATUS FOR THE MANUFACTURE OF C RUDE CALCIUM CYANAMID.

APPLICATION FILED JAN. 5 1917- 1,230,343. Patented June 19, 1917.

.10 mid from calcium carbi'd andhiitrogen a a UNITED STATES PATENTOFFICE.

NOBILE CARLO TOMMASI, OF BASEL, SWITZERLAND, ASSIGNOB TO THE FIRM F,ELEKTRIZITATSWERK LONZA, OF GAMLPEL AND BASEL,,-SWIT ZERLAND.

AIPPARATUS FOR THE MANUFACTURiE 0F CRUDE CALCIUM CYANAMID.

ipjall whom it M ay concern i-Be n, known that I, ,Xoinnn Can o Ton- MkS1, a subject of the King of Italy, re Siding at Basel, Sultzerland,have invented 5 new and useful Improvements in Apparatus for theManufacture of Crude Calciu n Cyanamid, of which the folloiving is afull, clear, and exact specification.

The production/of crude calcium cyai continuous process l1as11otyet beenachiev mainly because inthe processes liitherlo known "there has been nolpossihilityfwditiljusting the temperature withinl e' furnace to meetthe requirements of tlr 'In one procedure ithas been attempted toequalizet'the temperature. within a rotary furnace producing, 'F'tion ofthe nitrogen 'b'y means of n long, -'durat because tlfe nozzles becomechoked, l\'lt irer the attemptshon's that. it has not become known thatin the correct conduct of t ie process a notiurorthy portion of the heat(.lQYvluplrl by the reaction must be Withdi au'n, and morelfiflJl'l'lClllilI'lY that at the end of the reaction -IS nece erary tocool the proi'luct. in the 'l'ui- :e in nitrogen to avoiddeconipositiim.

The present inveniion'iiii HUS to a plant for theginan'ufacture 01 mincalcium cyanai'nid lroin calcium ca ml and nitrogen in arotiuyy furnace,in which for the purpose f l 'f t nntrollint the tenuf l'at lre in thefurl {the nitrogen is.nntiintained in constant, ,controlled circulationthrough heating and cooling deyices outside the furnacef Theaccompanying diagram illustrates the f improved plant partly in sideelevation, 40' partlyinsection.

" 'lhqiftary inclined furnace A is closed gastig'litja't both ends. Atthe higher end "a'thecalcium carbid eventually with addition oi:suhstanees faqilitating the reaction f and the nitrogen At the lower endi namid is removed thfoughgthe sealede' i and the circulatjag nitrogenintroduced through the pipe The pipes g' and a are connected toe'ther bya gas-tight pipe system m comiising a device v, such as a fan, forproduccirculation of thenitrogcn, a cooler r Janyd a heater s. The pipesystem also. comprises a dust chamber t from which a worm leayestirrijugh a'pipe, lr tue rude caleur Specification of Letters Patent.

lau-nted'lune 1-9, 1917.

917. Serial No. 140.796.

t:' 1r furnace,uneovered so that it. is cooled. by rz'uhatl'oiror inaybe artificially cooled.

'Jn order as faras possible. to prevent. the stream of nitrogen fromstirring up the dusty carbid and carrying it away, the. pipe 1/ isextended. as at 9 into the mouth of the furnace. whereby there isformed-at the upper end of the furnace, between the carbid pipe and thesaid extension, a chamber not traversed by the nitrogen, in whichchamber the carhid can with before it enters the reaction zone of the.urnace.

The operation is he follows:

For starting the operation. the tlurnace is heated to the temperaturenecessary for} the reaction before the eirciil'ation of nitrogen .isstarted. For this purpose, for example,

nitrogen may be heated in the heater 8 and blown into t l furnace. W'henthe-temperatureof reaction has been attained, introduction of calciumcarhid is started. Thefeeding of the car-bid is capable of control.Fresh nitrogen, if necessarypreheated, is introduced in suliicient'qmntity and the circulation of nitrogen is started. At first, in ordernot to cool the furnace a feeble circulation is maintained and thecooler .r .pre'ferably cut out of the circuit. If the.tem peraturefalls, it may be raised againnby s of the heater As, the reaction 6'fceeds and the rate of teeding-thecarhid; is iricreaserhthe temperaturegradually rises, heat being generat d by the reaction. In. proportion tothis rise the circulation andthe cooling of the nitrogen is increased,-The finihed cooled crude calcium. cyanamid is removed from the furnacethrough; the seal '11.

What I claim is:' j

1. In an apparatus for the manufacture of crude calcium cyanamid, arotary furnace of reaction, having calcium cal id feed device and .acalcium cyanam d discharge device, and a nitrogen circulating systembetween the endsref the furnace, ncluding nace as well as nitrogendisplacing means 1 to keep the nitrogen in constant, controlledcirculation through said heating and cooling devices outslde the furnacefor temperature regulating purposes, substantially as described.

2.'In an apparatus for the manufacture of crude calcium cyanamid, arotary fur nace of reaction, having a calcium carbid .feed device at itsone end and a calcium 'cyanamid discharge device at its other end,

the furnace part next to said discharge device being arrang lelad to becooled from without for aiding t e cooling of the finished product, anda nitrogen circulating system between the ends of the, furnace,including heating and cooling devices outside the furnace of reaction,having a calcium carbid feed device at its one end and a calciumcyanamid discharge device at its other end, and a nitro m clrculatingsystem between the ends 0 .the furnace, including nitrogen displacingmeans, heating and cooling means outside the furnace to kee the nitrogenin constant, controlled circulation through said heating andcoolingmeans, a chamber being provided at the feeding end of the furnace out ofthe circulating nitrogen path to allow settling of supplied calciumcarbid-before its entry to the reaction zone of the furnace,substantially as described.

In witness whereof I have hereunto signed my name. this 12th day ofDecember, 1916,

in the presence of two subscribing witnesses.

NOBILE CARLO TOMMASI,

